1. Field of the Invention
The present invention relates to an apparatus for control of exposure of a camera having an automatic exposure bracket mode drive mode (AEB mode) in which a plurality of pictures are taken while changing the exposure value within a predetermined exposure range.
2. Description of Related Art
A single-lens reflex camera having a photometer (brightness measuring device) and a distance meter (object distance measuring device) incorporated therein is known.
In such a single-lens reflex camera, the distance meter detects a distance (object distance) of an object to be photographed to move a focusing lens in accordance with the object distance thus detected, so that the focusing can be effected. On the other hand, the photometer detects the brightness of the object to determine a shutter speed or a diaphragm value in order to control the exposure in accordance with the brightness thus detected.
Generally speaking, such a single-lens reflex camera has various functions so as to respond to photographers' various requirements. These are, for instance, a continuous photographing mode at which a photographer can successively take pictures while a shutter button is pushed down; a programmed mode at which a combination of a shutter speed and a diaphragm value is determined; and an exposure adjustment mode at which an exposure is adjusted, etc. In particular, a camera is also known having an additional function of an AEB mode at which a plurality of frames of a film can be continuously taken with different exposure values within a predetermined exposure range (width).
However, in the camera mentioned above, it is necessary to provide special switches for the various function modes, resulting in an increased number of elements of a camera.
The primary object of the present invention is to provide an automatic exposure control apparatus of a camera having a decreased number of switches.
To achieve the object mentioned above, according to the present invention, there is provided an exposure control apparatus for a camera comprising, a first switch which can select a plurality of drive modes including at least an auto-exposure bracket mode (AEB mode), a second switch which emits signals when operated, a third switch which can modify an exposure correcting value, and a memory which stores a plurality of predetermined exposure correcting values. A drive mode selecting mechanism which successively selects the drive modes in response to signals which are issued from the second switch when the second switch is actuated during the operation of the first switch is provided and a modifying device for successively selecting an exposure correcting value to be used to correct the exposure value among those stored in the memory in response to signals emitted from the second switch when the latter is actuated during the operation of the third switching is also provided. A photographing control means for taking a plurality of pictures at different exposure values in an exposure width which corresponds to the exposure correcting values selected by the modifying device when the AEB mode is selected by the drive mode selecting mechanism is provided.
According to another aspect of the present invention, there is also provided a camera having a plurality of drive modes including at least an auto-exposure bracket mode (AEB mode), comprising, a first switch a, second switch a, third switch means and a, memory for memorizing exposure correcting values with a, drive mode selecting mechanism which successively selects the drive modes when both the first and second switches are simultaneously actuated and which sets a selected drive mode when the operation of at least one of the first and second switches are released is provided. A modifying device which successively modifies the exposure correcting values at a predetermined step when the third and second switches are actuated and which stores a modified exposure value correcting value in the memory when the operation of at least one of the third and second switches is released is provided. A photographing control means for taking a plurality of pictures at different exposure values in an exposure width which corresponds to the exposure correcting value stored in the memory means when the AEB mode is selected by the drive mode selecting mechanism is provided.
With this arrangement, the drive modes are selected by the selecting mechanism in accordance with the operation of the second switch only when the first switch is actuated. The exposure correcting value which is stored in the memory is changed by the modification device in accordance with the operation of the second switch only when the third switch is actuated. When the automatic exposure bracket mode is selected by the selecting mechanism, the photograph control means performs the photographing with different exposure values within an exposure width which is determined by an exposure correcting value stored in the memory or an exposure correcting value modified by the modification device.